ISO 29461 specifies methods and procedures to determine the performance of particulate air filters used in air intake filter systems for rotary machinery such as gas turbines, compressors and other internal combustion engines. The ISO 29461-3 specifies a method and procedure to test the mechanical integrity ( Burst Test ) of individual filter elements up to an abnormal final test pressure drop of maximum 6 250 Pa. Any other customer defined final pressure drop up to a higher pressure drop shall be reported as variation from the standard. Nevertheless, it is within the ability of the user to define the maximum possible value (lower or higher) for a certain application and to define the burst strength requirements for this test procedure. As the pressure drops under typical operating conditions are on a much lower level, it is not intended to specify a final pressure drop for any application within this procedure. This procedure is intended for all types of filter elements (e.g. V-bank cassette filters or filter cartridges) used in the final stage(s) of an Air Intake Filter Systems for Rotary Machinery in various environmental conditions, as e.g. in marine applications. These filters are operating at flow rates within the range of 0,24 m3/s (850 m3/h) up to 2,36 m3/s (8 500 m3/h), no matter if used in a static or pulse cleaned air intake system. Note It should be considered that the pressure drop increase versus dust loading of filter elements with lower efficiencies (e.g. not the final stage(s) of the filter system) is relatively low and can lead to protracted test durations. The user should define the filter stage(s) relevant to withstand abnormal high pressure drops in application. Filter elements with a lower efficiency than ISO T5 (ePM10) according to ISO 29461-1 are excluded. As a standard to ensure the comparability of the test results only new filter elements or those loaded up to 625 Pa or maximum 800 Pa according to ISO 29461-1 shall be tested. In general, it is possible to use this procedure also after any previous ageing procedure if it is clearly described as a variation from the standard test procedure. An ageing procedure is defined as an appropriate customer defined durability test which can affect the stability of media, adhesives, construction etc. and is important for the evaluation at its real application. Test results of filter elements after different ageing procedures may not be quantitively compared. Examples of conditioning are: Climatic conditioning at high or low temperatures and/or defined relative humidity levels Wet conditions with water droplets or condensing water over a defined time period Any kind of dust loading and pulsing procedure over a certain duration or number of pulses Operation at real conditions etc. The Burst Test itself is considered as an independent procedure to evaluate the integrity of a filter element to resist a defined high pressure drop without collapsing, losing or releasing any parts of its construction into the downstream while keeping its filtration efficiency. The ISO 29461-3 does not describe a standardized method to measure the fractional or gravimetric efficiency. It is recommended to test the efficiency of the filter element according to ISO 29461-1. The performance results obtained in accordance with this standard cannot be quantitatively applied (by themselves) to predict performance in real use1). The test procedure does not include methods for the direct measurement of the performance of entire systems as installed, e.g. systems with use of multiple stages of coarse and fine filter elements.